Lima Aline P A S, Silva Kelly, Padovan Cláudia Maria, Almeida Sebastião Sousa, Fukuda Marisa Tomoe Hebihara
Department of Ophthalmology, Otorhinolaryngology and Head and Neck Surgery, Ribeirão Preto Medical School, University of São Paulo, FMRP-USP, Brazil.
Department of Psychology. Faculty of Philosophy, Sciences and Letters of Ribeirão Preto, University of São Paulo, FFCLRP-USP, Brazil.
Behav Brain Res. 2014 Feb 1;259:247-52. doi: 10.1016/j.bbr.2013.10.046. Epub 2013 Nov 13.
The present study demonstrates the consequences of animal exposure to an enriched environment compared to animals living in a standard environment regarding learning and space memory. Male albino Wistar rats were exposed to an enriched environment for 4 weeks after the lactation period and tested in the Morris water maze in the distal and proximal clue version and in the arena. In the former test, the animals were tested at 50 days of age with 12 daily trials on two consecutive days. At the end of each session, scopolamine at the dose of 0.6 mg/kg/ml or saline solution was injected intraperitoneally. Twenty-eight days after the first phase, a new test consisting of a single trial was held (retest). An independent group of animals receiving no drug was subjected to the arena test and to the proximal clue version of the Morris maze. In the distal clue version the results did not show differences between groups in the first phase of the experiment. After 28 days (retest), the animals reared in a standard environment and treated with scopolamine exhibited a significant increase in latency compared to the group receiving the same drug and stimulated and to the group receiving saline. The arena data demonstrated a significant increase in exploratory activity in the group of animals reared in an enriched environment. The proximal clue version of the Morris maze did not show differences between groups. The results of the present study indicate that animals exposed to environmental enrichment react less to the amnesic effects of scopolamine and show an increase in exploratory activity.
本研究展示了与生活在标准环境中的动物相比，处于丰富环境中的动物在学习和空间记忆方面的结果。雄性白化Wistar大鼠在哺乳期后暴露于丰富环境中4周，并在远端和近端线索版本的莫里斯水迷宫以及竞技场中进行测试。在前一项测试中，动物在50日龄时进行测试，连续两天每天进行12次试验。在每次试验结束时，腹腔注射剂量为0.6mg/kg/ml的东莨菪碱或生理盐水。在第一阶段后的28天，进行了一项由单次试验组成的新测试（重新测试）。一组未接受药物的独立动物接受竞技场测试和莫里斯迷宫的近端线索版本测试。在远端线索版本中，实验第一阶段各实验组之间未显示出差异。28天后（重新测试），与接受相同药物并受到刺激的组以及接受生理盐水的组相比，饲养在标准环境中并接受东莨菪碱治疗的动物潜伏期显著增加。竞技场数据表明，饲养在丰富环境中的动物组探索活动显著增加。莫里斯迷宫的近端线索版本各实验组之间未显示出差异。本研究结果表明，暴露于环境丰富化的动物对东莨菪碱的失忆作用反应较小，并表现出探索活动增加。
